Treatment of sewage and the like.



N. TESTRUP.

TREATMENT OF SEWAGE AND THE LIKE APPLICATION FILED FEB-7, 1912.

Patented Nov. 10, 1914.

' flrlameya UNITED STATES PATENT OFFICE.

NIES TE STRU I, OF EONDON, ENGLAND, ASSIGNOR, BY MESNE ASSIGNMENTS, TO WET- cannomzmc LIMITED, or ennon, ENGLAND.

TREATMENT OF SEWAGE AND THE LIKE.

Specification of Letters Patent.

Patented Nov. 10, 1914.

To all whom it may concern:

Be it known that I, NILs Tnsrnur, a subject of the King of Great Britain and Ireland, and resident of 6 Broad Street Place, London, E. 6., England, have invented certain new and useful Improvements Relating to the Treatment of Sewage and the like, of which the following is a specification.

This invention relates to the treatment of sewage or the like and has for its object to provide an improved process of disposal for such matters allowin of eifecting this more cheaply than hereto ore and in some in stance without cost. This result is largely obtained by the recovery of valuable'constituents of the substances.

It has been observed that when sewage is heated to a temperature of 130 C. or above, there has apparently occurred complete coagulation of the dissolved and suspended organic solids, for the liquid can after such treatment be readily filtered and press cakes of relatively low water content easily obtained.

This process can therefore be employed for the removal of the solid matters from sewage more cheaply and efficiently than heretofore, since by using suitable apparatus of high efficiency little heat need be consumed and as sterilizing is no longer the object, excessively large volumes of liquid do not need to be handled, the chief portion of the liquid being separated in settling tanks or otherwise and a concentrated liquor heated by this process while at the same time by recovering or utilizing valuable constituents of the resultant solids, the cost of the process can be still further reduced.

This invention therefore consists in applying such a process to the treatment of sewage for the purpose of removing solid matters therefrom, the sewage being preferably subjected to a, preliminary concentration by settling or the like, say until it contains 7 70 or thereabout of solid matter.

In carrying the invention into efi'ect in one form the sewage which has had its water content somewhat reduced is caused to enter an autoclave.

The accompanying diagrammatic drawings show an apparatus suitable for carryin out the process.

igures 1 and 1 show the installation in side elevation, and Fig. 2 a, detailed part sponds to a pressure of about 25 lbs.

outer one being closed at one extremity (see Fig.2) and the material entering at the opposite end and between the tubes and returning by the inner-tube '5 toissue from the apparatus. That-extremity ofthe tube system which isclosedi-endedis placed in a furnace s or otherwise suitably heated, and byadjusting the relat on 'bgtweeu the. inflo outflow, a sufficient pressure can be caused to exist in the apparatus to prevent ebullition, and thus to enable the material contained in the apparatus to be raised to the required temperature while yet permitting a continuous flow. When the temperature used is only about 130 0., which correer square inch, the walls of the tube neediiot be excessively thick. Experiments have shown that the higher the temperature employed the easier is the subsequent separation of the precipitated matters from the liquid, and for best results, the temperature should not fall below about 130 C.

As, in an apparatus of the character described, the entering and outflowing matters are continuously flowing at a relatively rapid rate and in thin films on opposite sides of the separating wall, a high rate of transmission and a large degree of exchange is obtainable thereby.

The sewage which has passed through the apparatus, can be readily filtered in a filter press X, or otherwise to be subsequently treated for the removal of water and fatty matters. sponding to the vapor tension at 130 C. or more) at which the liquid leaves the apparatus, or a portion thereof, may be used as the pressure for the filtration by supplying the liquid directly into a filter press. The liquid efiiuent may be discharged at any suitable spot as it is practically devoid of smell. The eflluent moreover is readily filtrable and will not if discharged on to land in a short time clog the same and render it no longer capable of taking up any more as occurs at present.

The high pressure (that corre- It will be observed that by heating the sewage in an autoclave to effect the coagulation of the albuminous matters, and the car-- bonization or other decomposition of the colloidal and similar matters rendering filtering easy, the addition of foreign materials to the sewage such as lime or the like as in existing processes becomes unnecessary. It may be possible in certain cases to use the press cake material directly for heating the autoclave.

The final result of the present process is that there isno sludge to be carried to any considerable distance, dumped, or otherwise disposed of, and it-vbecomes only necessary to get rid of an efiluent which is practically clear water. I

Having now described my invention what I claim as new and desire to secure by Letters Patent is:' I g 1. A method of'rend'ering the water of sewage sludge readily expressible, consisting in raising the temperature of said slud e rapidly 'to a temperature above 100 moving while under ressure, maintaining it for a short time o y at this temperature, rapidly cooling it to a temperature below the boiling point of the accompanying water, and separating water therefrom by pressure, as set forth. 7

2. A method of treating sewage consisting in separating a fluid sludge therefrom by settlement, raising said fluid sludge While in rapid motion and under pressure to a temperature above the boiling point of the associated liquid, maintaining said material at this temperature until the slimy matters have become completely coagulated, transmitting the heat of said sludge to a quantity of cooler sludge about to be heated, and rewater from the already treated sludge by filtration under pressure.

In testimony whereof I atfix my signature in the presence of two witnesses.

I NILS TESTRUP. Witnesses:

T. ZACLAN, I H. MA'I'I'HEWS. 

